Magnetic calculator and indicator



Sept. 29, 1925.

J.A.HOGSTEN ETAL MAGNETIC CALCULATOR AND INDICATOR Filed Jan. 8. 25

Patented Sept. 29, 1925.

UNITED STATES 1,555,575 PATENT, OFFICE.

JAMES A. HOGSTEN AND WILEY A. KILGO'RE, or BANKHEAD, ALABAMA; sAIn HOG-v s'rnn ASSIGNOR T0 JAMES R. usnnv, oruaAnKHnAn, ALABAMA.

MAGNETIC cA cuLAron Ann INDICATOR.

Application filed January 8, 1925. semi m. 1,275.

To all whom it may concern: 7

Be it known that we, JAMES A. Hmsrnn and WILEY A. Kinconn, citizens. of the United States, residing at Bankhead, in the county of Walker and State of Alabama, have invented certain new and useful I1n provements in Magnetic Calculators and Indicators; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it apper- Itains to make and use the same.

The primary object of this invention is the provision of an attachment to be applied to or form the back of a tablet, said attachment including a calculator and indicator for designating the product of a multiplicand and multiplier, said attachment comprising a rotatable disk provided with'numbers in sets, each set including a multiplicand and multiplier, and said disk being provided with an attractor such as steel or iron to draw. a magnetic needle which is movable over a dial containing numbers which represent the products of the several sets of numbers provided on the said rotatable disk, the magnetic needle indicating the product of the set of numbers exposed to view through an observation opening of the dial.

Other objects and advantages will be apparent and suggest themselves as the nature of the invention is understood.

While the drawings illustrate an embodiment of the invention it is to be understood that in adapting the same to meet difl'erent conditions and requirements, variouschanges in the form, proportion and minor details of construction may be resorted to without departing from the nature of the invention. 1

Referring to the accompanying drawings forming a part of the specification,

Figure 1 is a planview of an article of the nature aforesaid embodying the invention,

Figure 2 is a sectional view on the line 22 of Figure 1, 5

Figure 3 is an enlarged sectional view 0 the central portion of the article,

Figure 4: is a front view of the rotatable disk provided with the attractor and the set of numbers such as the multiplicand and Corresponding and like parts are referred to in the following description and des1gnated in the several views ofithe drawings by like reference characters.

The numeral 1 denotes the dial-which corresponds to the back of the tablet or other supporting base upon which appears numbers 2 arranged in a circle and corresponding with the products of the several sets of numbers provided upon a disk 3 located in the rear of the dial 1 and pivoted thereto,

9 multiplied by 7 opposite the observation opening 6 and'the product of such numbers is designated by a hand or magnetic needle 7 which points to the number 63.

An attractor 8 is mounted upon the, disk 3v and preferably consists of iron or steel which is susceptible of being magnetized or to attract a magnet such as the needle 7 which is mounted to turn freely. The attractor 8 is fast to the disk 3 and its ends 9 are thickened so as to extend through openings formed in the disk 3 and come about flush 'with the face thereof bearing the sets of numbers 5 and as the disk 3 is rotated the attractor 8 moving therewith attracts the hand or magnetic needle 7 so as to properly position the same on the dial 1 to indicate the products of the numbers appearing opposite the observation opening 6.

The base 1 is relatively thick and the hand or magnetic needle 7 is mounted and is free to turn to follow the movements of the attractor 8 and the disk 3 is mounted so as to be turned to bring any required set of numbers to be multiplied opposite the opening 6 when the product will be indicated on the dial by the hand 7 as shown most clearly in Figure 1. The several parts are concentrically mounted, the pivot connection 10 being of any preferred construc tion best adapted for the purpose. A backby the disk to cause the magnetic hand to follow the movements of the disk and designate the product of the numbers appearing opposite the said observation opening.

2. A magnetic calculator and indicator comprising a dial having an observation opening and provided with a plurality of product numbers arranged in a circle, a magnetic hand movable over the dial, a disk disposed in the rear of the dial and provided with sets of numbers arranged in a circle, each set of numbers including a multiplicand'and a multiplier, and a magnetic attractor carried by the disk and located in the rear thereof and having its ends extended into openings formed in the disk, said attractor causing the magnetic hand to follow the movements of the disk to indicate the product of the set of numbers appearing opposite the said observation opening.

In testimony whereof We aflix our signatures.

JAMES A. HOGSTEN. WILEY KILGORE. 

